Attachment for milling machines



B. F. JOHN-SON.

ATTACHMENT FOR MILLING MACHINES.

APPLICATION nuso JUNE 1. 1920.

1 40 70 Patented Feb 14, 1922.

machine illustrating UNITED STATES PATENT OFFICE.

BERNARD F. JOHNSON, 0Z1 JERSEY CITY, NEW JERSEY.

ATTACHMENT FOE MILLING MACHINES.

Application filed June 7,

To all whom it may concern:

Be it known that I, BERNARD F. JOHNSON, a citizen of the United States, residing at Jersey City, in the county of Hudson and State of llew Jersey, have invented certain new and useful Improvements in Attachments for Milling Machines, of'which the following is a iulhclear, and exact description.

This invention relates to devices for accurately laying out work,and more particularly to attachmentsi'or milling machines. In laying out workpreparatory to machining or drilling the same, the mechanic customarily by the use of: scales, calipers, etc., measures oil upon the work the required dista-noes from. any reference points or edges and then with a prick punch produces a slight indentation in the surface which acts as a guide in the subsequent machining or drilling operations. Due to the unsteadiness of the human hand, some error in this kind of work always occurs, the amount varying with the skill of the particular mechanic. An object of .my invention is to provide improved means for laying out work which will reduce the human error to a minimum, which will enable the satisfactory employment on such work of ordinary mechanics, and which is inexpensive, and simple, accurate, and rapid in operation. Other objects and advantages will beapparent from the following description and the novel features of my invcntion will be particularly pointed out in claims My invention comprehends the provision of a prick-punching or marking device which can be readily attached in any of a plurality of different positions to the arbor or other convenient part of a milling machine, or similar machine, upon the table, or adjustable portion of which the. work to be laid out is mounted, so that the adjustments of the table or other adjustable portion can be'employed as the measuring instrument.

In the drawings: 1

Fig. 1 is a perspective sketch of a milling the method of attachment thereto of my improved device.

: Fig. 2, is a side elevation of the preferred embodiment of my device.

Fig. .3 is an end elevation of the same.

Fig.4 is a plan of an arbor with my de vice attached thereto, and

' a diagramillustrating the pro Specification. of Letters Patent.

Patented Feb. 14, 1922.

ment a marking device 6 which preferably comprises a prick-punch of tempered steel, having a conical punching point 7. The punch is provided along its length with collars 8 and 9 which are disposed on the same at opposite ends of the extension 8. A spring 10 reacts between the collar Sand the adjacent end of the extension 3 to yieldingly hold the punch in retracted position, the extent of retraction being determined by the engagement of the collar 9 with the end of the extension 3 adjacent to it. A' set screw 11 in the extension 3 is arranged to contact with the shank of the punch and adjustably secure the latter in any of the sliding positions which it may assume in the extension.

The member 1 may be mounted upon the arbor 12 of a milling machine by the passage of theshank of the arbor tl'n'oughone of the apertures l or 5 in the enlarged head 2. The member 1 may be located at any desired position along the arbor by spacing rings 13 disposed between'the member and the flange 1e and nut 15 of the arbor (Fig. 4:). Tightening of the nut 15 serves to frictionally clamp the member 1 in any desired angular position about the arbor. The arbor has the usual tapered end 16 by which it is supported in. the spindle 17 of the machine. In milling machines, the table 18 may be adjusted upon the frame 19 in an endwise direction by suitable mechanism operated by a handle 20', the extent of movement being indicated by the scale 21. The table. may be adjusted forwardly and rearwardly by suitable mechanism operated by a handle 22, the extent of movement being indicated by a scale 23. The table may be adjusted vertically by the handle 24:, the extent of move ment being indicated by the scale 25.

In use, the work to be laid out is first mounted upon the table with the working face upon which the measurements are to be laid ofi arranged as nearly possible in l is then arranged upon the arbor with the punch substantially perpendicular to. the working face, and depressed against the action of spring 10 in which position it .is clamped by set screw ll. The handlesin control of the table are then manipulated to bring the work with a reference edge against the side of the punch shank. This locates the work with respect to the puncl for laying off distances in one direction, and this position may be diagrammatically iilus trated in Fig. 5, wherein the workine iace is designated 26 and the position or the punch as 2? abutting the reference edge 28. The shank of the punch is accurately ground to a known diameter, so that when the parts are in a reference position the radius oi the shank should be added to the distance through which the work must be moved with respect to the punch in oreerto bringthe' point 7 of the punch exactly over the desired line or point. The set screwis operated to release the punch which springs hack to clear the work. The table is-thcn operated by the proper handle to shift the work relatively to'the punch. say along the theoretical line (r.7) (Fig. any desired distance such as that indicated between the edge 28 and the theoretical line cd. This movementis then temporarily ended, and another handle operated'to shift the work along the line c-d to bring a reference edge 29 against the shank of the punch which is now represented at 30.. The punch may again be temporarily clamped in depressed position bye-crew 11 during this location as well as in the first one, and after the location has beenthus made is again released. The work can now be shifted by the same handle along the line 0-(Z to bring the edge 29 the desired distance from the punch position 30 (the radius of the punch being added to the distance meas ured off upon the scale of the handle being operated). The point of the puncu will now be adjacent the working surface and at an exact known distance from edges 28 and 29. A hammer may be used to tap the blunt end of the punch'and cause the point 7 to prick the surface of the work. The table may thereafter be shifted known and measurcd distances in any directions to accurately locate other points, and the surface pricked by tapping of the blunt"end of the punch, some of the possible positions being indicated by way oi example, by the small crosses 31 in Fig. 5. By the use of the scales and the handles of such machines the measurements and punchings can be accurately made without the inclusion of on rors due; to the unsteadiness of the human hand. It is of course to be understood that the spindle of the machineis not to be rotated during the layingoult operation, the idea being, merely to utilize the accurate table adjustments or those of dividing the reference head upon the table, with the spindle or other part of the machine as the support for the marking device. The lines referred to in laying out the work are theoretical. lines since my invention eliminates the actual laying of lines. While I have illustrated only a horizontal milling machine, it is obvious that the attachment can be equally well applied to a vertical spindle. While I have for convenience referred to the application of the device to a milling machine, it is to be understood that this is illustrative only of a type of machinehaving table adjusting means for accurately measuring distances, to which I refer. Any machine having accurate adj ustmeutstor a work carrier which can be moved through measured distances may he employed, in which case the attachmentmaybe clamped or otherwise secured to any convenient part of machine. Various other changes in the details of construction herein de scribed and illustrated may obviously be made within the invention.

I claim I j An attachment tor milling machines or the like provided with an arbor, said attachment comprising an arm having aplurality of intersecting apertures in one end there of through any of which said arbor of the machine may pass for the purpose of s'ecui'} ing the arm to the arbor, and a marking device carried by the other end of the armi 2 An attachment for milling machines or the like, provided with an arbor, said attachment comprising an arm having'a plurality of apertures in one end thereof through any of which said arborof themachine may principle and scope of my pass for the purpose of attachment of the 3 arm to said arbor and a prick-punch slidably mounted in the other end of the arm.

3. An attachment for millin machines 'or the like, provided with said EIIbOlQjSitld at-- tachment comprising an armhaving a phirality of intersecting apertures in'one end thereof through any of which said arbor may pass for the purpose of securing the'arm to the arbor, in different relative positions,

a prick-punch mounted gt'orendwisem'ovement in said arm, means for'hmiting movement of thepuneh 1n a contra-punchmgdlrection, and means for" yieldingly holding the punch at the limit of movement in said direction. f

4. .An atachment for milling machinesfor the like provided with said arborfsaid attachment.comprising an arm' having a. plurality of intersectingaperturesin omens thereof through any ofwhich said arbor may pass forthe purpose. of securing said arm to said arbor indifferent relative positions, a prick-punch mounted for endwise movement in said arm. means for limiting mg direct-ion, means for yieldin'gly' holding movement ofthe punch in a contra-punch i the punch at the limit of movement in said direction, and a set screw carried by the arm and engaging the punch to lock it in adj usted positions in the arm.

5. In combination with milling machine or the like having an arbor, a table, means for adjusting the table in a plurality otnonparallel directions, and means for indicating the amount of each adjustment, of an arm carried by said arbor, and a marking device carried by the arm and shiftable at will to engage and mark the surface of work carried by the table.

6. In combination with a milling machine or the like having an arbor, a table, means for adjusting the table in a plurality of directions transverse to one another, and means for indicating the amount of each adjustment, of an arm carried by said arbor, and a prick punch carried by said arm for movement toward and from the work upon the table.

7. In combination with a milling machine or the like having an arbor, a table, means for adjusting the table in a plurality of nonparallel directions, and means for indicating the amount of each adjustment, of a member attachable to said arbor in a plurality of different positions, and a marking device carried by said member for movement toward and from work upon the table.

8. In combination with a milling machine or the like having an arbor, a table, means for adjusting the table in a plurality of nonparallel directions, and means for indicating the amount of each adjustment, of a member attachable to said arbor in a plurality of different positions in which the axis of the bearing is in non-parallel positions with respect to itself and a punch carried by the member for sliding movement toward or from work upon the table.

9. In combination with a milling machine or the like having an arbor, a table, means for adjusting the table in a plurality of nonparallel directions, and means for indicating the amount of each adjustment, of a member, a punch slidable in said member, means normally tending to retract the punch, means for limiting the retractile movement, said member being attachable to the arbor in a plurality of different positions in which the punch is in angular positions with respect to itself.

In witness whereof, I hereunto subscribe my signature.

BERNARD F. JOHNSON. 

